The synthesis of quantum dots is known in the art. US2012104325, for instance, describes an isolable colloidal particle comprising a nanoparticle and an inorganic capping agent bound to the surface of the nanoparticle, a solution of the same, a method for making the same from a biphasic solvent mixture, and the formation of structures and solids from the isolable colloidal particle. The process can yield photovoltaic cells, piezoelectric crystals, thermoelectric layers, optoelectronic layers, light emitting diodes, ferroelectric layers, thin film transistors, floating gate memory devices, imaging devices, phase change layers, and sensor devices. Especially, this document describes an isolable colloidal particle comprising an inorganic capping agent bound to a surface of a nanoparticle and substantially free of an organic capping agent. Further, this document describes a solution of such colloidal particle comprising a solvent and the inorganic capping agent bound to a surface of a nanoparticle, wherein the solution is substantially free of an organic capping agent.
WO2013057702 describes a luminescent nano particles based luminescent material comprising a matrix of interconnected coated luminescent nano particles, wherein for instance wherein the luminescent nano particles comprise CdSe, wherein the luminescent nano particles comprise a coating of CdS and wherein the matrix comprises a coating comprising ZnS. The luminescent material according may have a quantum efficiency of at least 80% at 25° C., and having a quench of quantum efficiency of at maximum 20% at 100° C. compared to the quantum efficiency at 25° C.
WO2012035109 describes mixed crystals made of semiconductor materials from the elements of groups 12 & 15, 12 & 16, 13 & 15 and/or 14 & 16 of the periodic table of the elements in a protective matrix, to a method for producing same, and to the uses thereof in various materials, for example in fluorescent tubes, in laser technology or as packaging material for nanoparticles. The semiconductor particles have an average size between 1 and 100 nm and the content thereof in the mixed crystal is 10-9-10%.